Safety circuits are known from the prior art. Such a system is, for example, disclosed in German Patent Application No. 10 2008 061 564. So-called actuators are monitored by a control unit and, when an error is identified, the relevant actuator is deactivated, for example, by shutting off the output stage. A second actuator is enabled to restore a safe system status, for example, by disengaging its clutch.
A disadvantage of this arrangement is that monitoring cannot be performed when there is an error in the control unit, or during a reset state, or when the connection is faulty between the control unit and actuators. If both actuators were shut off in this case, a safe system state could not be achieved.
Thus, there is a long-felt need for improved safety circuitry that avoids one or more disadvantages of the prior art and contributes to greater system safety.